All of America’s most important airlines operate what are known as hub-and-spoke networks. Airlines like Delta Air Lines, United Airlines, and American Airlines are classified as full-service-network carriers, and they primarily focus on serving business travelers and higher-end leisure travelers, with budget airlines and other non-traditional carriers seeking to target more price-sensitive travel demographics. A core element of the legacy airline operating model is the hub-and-spoke system, which involves funneling passengers through large connecting hubs to provide as efficient access to as many destinations as possible.